Pakistani militants are being linked to polio's reappearance in Syria, which had been polio-free since 1999.

The Middle Eastern country has 13 reported polio cases so far this year, the World Health Organisation (WHO) said in a statement November 12th. Genetic sequencing showed the strain of virus found in Deir al-Zor Province, Syria originated in Pakistan.

The reasons militants are believed responsible are two-fold.

First, the Tehreek-e-Taliban Pakistan (TTP) does everything it can – from attacking and sometimes killing vaccination team members, to threatening parents and their children – in order to stop Pakistanis in the tribal region from getting the Oral Polio Vaccine (OPV).

That campaign left one million children in Pakistan's Federally Administered Tribal Areas (FATA) vulnerable to the disease, physician and FATA Polio Officer Muhammand Shoiab said.

"Taliban militants are responsible for crippling 43 children in FATA in 2013, and are likely responsible for infecting children in foreign countries," Shoiab said, adding the 43 children could have been saved had they been vaccinated.

Second, militants who receive training in Pakistan can pick up the virus and carry it wherever they go afterward.

"Militants have a history of transporting virus to foreign countries," said physician Mushtaq Khan of Prime Minister Mian Muhammad Nawaz Sharif's PolioMonitoring Cell. "The virus often infects children under five years old, but it can stay in faecal matter of adults, and then [flies can transmit the virus] to children."

"So the argument by the Syrian government blaming the virus transmission on the militants who allegedly went from Pakistan to fight alongside rebels isn't misplaced," Mushtaq said, referring to recent comments by Syrian Minister of Social Affairs Kindah al-Shammat.

TTP allows polio virus to survive

TTP militants have a long history of hampering Pakistan's anti-polio efforts. They say the vaccine is a Western ploy to keep the Muslim population from growing and falsely claim OPV can sterilise those who receive it.

Since December 2012, the Taliban increased efforts to stop administration of the vaccine, assassinating 30 health workers and the policemen guarding vaccination teams in Khyber Pukhtoonkhwa province and Karachi.

The Taliban's opposition to the OPV violates the tenets of Islam, but convincing the public to defy the militants is difficult, religious scholar Mufti Inamullah Shah said.

"According to Islamic injunctions, we are bound to safeguard our children against diseases," he said. "All parents want to protect their children against disabilities, but they are afraid of the Taliban."

Because of the TTP's fierce opposition to the OPV, Pakistan is one of only three countries where polio is still endemic. The other two are Nigeria (with 51 reported cases this year) and Afghanistan (with nine cases)—other countries where extreme religious fundamentalism holds powerful control over aspects of daily life. Pakistan reported 62 cases so far this year, surpassing all of 2012.

Ramifications of polio in Syria

With polio's reappearance in Syria, WHO fears the malady could spread across the Middle East. Over the past year, WHO medics detected a virus closely linked to the Syrian strain in Egypt, Israel and in the Palestinian territories.

The agency stepped up efforts to respond should the virus appear elsewhere. Vaccination campaigns are planned to cover 22 million children in seven countries and territories, AFP reported.

"The role of a few endemic countries in reinfection is dangerous," said Elias Durry, WHO Emergency Co-ordinator for Polio Eradication in Pakistan. No country is safe as long as the virus circulates somewhere in the world, he added.

Pakistan is working to contain further spread of the virus.

"We are taking measures to prevent the virus from being transmitted outside our borders," Mushtaq said. The government has instructed provincial governments to set up permanent vaccination counters at airports' international departure lounges to vaccinate everybody against the virus, he said.

This article originally appeared in Central Asia Online